In the event of managing mobile agents or in the event that a user sends or restores a message for his or her own agent issued in the past, it is necessary to manage information of where the mobile agents are located now.
For instance, a method for tracing locations of mobile agents by logging is disclosed in “GMD FOKUS and IBM Corp., Mobile Agent System Interoperability Facilities Specification, OMG TC Document (orbos/97-10-05), November 1997 ([MASIF]; Document 1).
Also, a method for tracing locations of mobile agents by a registry is disclosed in the above Document 1 and “GrassHopper—A Mobile Agent Platform for IN Based Service Environments, Proceedings of IEEE IN Workshop 1998, pp. 279-290, May 1998 ([GrassHopper]; Document 2).
On the other hand, the following are required for management of locations of mobile agents due to its nature: (1) immediacy of information to inquiry whereby one is capable of providing up-to-date information; (2) high traceability, such that, in case of a failure in distributed surroundings, one is capable of tracing as many agents as possible in as short a time as possible until restoration; (3) scalability, whereby one is capable of supporting a larger number of agents or more accumulated number of movement; and (4) low cost for information management whereby small overhead is involved in movement of agents.
However, the methods disclosed in the above Documents 1 and 2 do not meet these requirements sufficiently.
It is therefore an object of the present invention to provide an apparatus and a method for managing mobile agents that meet demands of location management of mobile agents in a higher quality.